Record-playback manipulator system utilizing hydraulic microbit actuators

ABSTRACT

A pulse generator common to all of the controlled axes of the manipulator arm is employed to develop a stream of pulses which may be selectively applied to the count up or count down lead of a bidirectional counter. Individual stages of the counter control individual pressure sensitive hydraulic actuators which are arranged in a series and have binary related strokes. Accordingly, the arm is moved in each axis in response to the pulse stream and at a rate corresponding to the rate of occurrence of pulses in said stream during the initial teaching operation. A series of limit switches are employed to detect the physical position of the series of actuators during the repeat mode of operation of the manipulator. These limit switches are also employed to set each bi-directional counter to an initial setting corresponding to the physical position of the arm on start up so that undesired movement of the arm at start up time is avoided.

United States Patent [1 1 Dunne [451 Sept. 17, 1974 RECORD-PLAYBACKMANIPULATOR SYSTEM UTILIZING HYDRAULIC Primary ExaminerEdgar W.Geoghegan I Assistant ExaminerA. M. Zupcic MICROBIT ACTUATORS Attorney,Agent, or FirmMason, Kolehmainen, [75] Inventor: Maurice J. Dunne,Fairfield, Conn. Rathbum & wyss [73] Assignee: Unimation, lnc., Bethel,Conn. 57 ABSTR CT A [22] Filed: May 14, 1973 1 A pulse generator commonto all of the controlled [21] Appl 359697 axes of the manipulator arm isemployed to develop a stream of pulses which may be selectively appliedto [52] US. Cl. 91/35, 91 /167 the count up or count down lead of abidirectional [51] Int. Cl. Fl5b 11/18 counter. Individual stages of thecounter control indi- [58] Field of Search 91/35, 36, 37, I67, 361,vidual pressure sensitive hydraulic actuators which are 91/363 arrangedin a series and have binary related strokes.

1 Accordingly, the arm is moved in each axis in response to the pulsestream and at a rate corresponding [56] Referen Cited to the rate ofoccurrence of pulses in said stream dur- UNITED PATENTS ing the initialteaching operation. A series Of limit switches are employed to detectthe physical position w g of the series of actuators during the repeatmode of 3:125856 341964 /363 R operation of the manipulator. These limitswitches are 1141:3138 7/1964 Brandstadter 91/167 also employed to seteach bi-directional counter to an 3,162,365 12/1964 Gizeski 91 I167initial Setting corresponding to the P y Position of 3,550,630 12/1970Panissidi 91/35 the arm on start up so that undesired movement of the3,661,051 /1972 Dunne 91/35 arm at start up time is avoided.

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I4 l Is 2s 34 36 l I 20 74 l I TEACH CONTROLS IZ I 5 66 g? l I w gyrCOUNT UP l I PM 2 2 2 2 I r m COUNT] DOWN I Lf ii li il i fi J so 52 F h4 g ROEPEAT -l SWIVEL AXIS 82 PULSE g SHAPER TEACH 8 J2{IVHIIYIELSWITCHES H DOWN-UP AXIS I L-- DOWN-UP LIMIT SWITCHES I k h a92 BEND AXIS I BEND LIMIT SWITCHES I 94 -I ROTARY AXIS I I ROTARY LIMITSWITCHES RECORD BUTTON RECORD-PLAYBACK MANIPULATOR SYSTEM UTILIZINGHYDRAULIC MICROBIT ACTUATORS The present invention relates tomanipulator apparatus and, more particularly, to an improved arrangementfor providing both record and playback facilities in a manipulatorapparatus of the type which employs hydraulic microbit actuators.

In certain types of manipulator apparatus heretofore proposed, it iscontemplated that the actuator for controlling each controlled axis ofthe manipulator arm will each comprise a series of fluid pressureactuators which are mechanically connected to one another and arrangedwith binary related strokes so that a binary code command signal can beapplied bit by bit to different hydraulic actuators in the series,thereby eliminating conventional digital to analog converters, etc. Onesuch arrangement is shown in Devol US. Pat. No. 3,476,266 wherein aseries of fluid-pressure actuators, each having an extended state and acontracted state, are operable in various combinations to providearelatively high power driving output by collectively changing inoverall size. While the arrangement shown in Devol US. Pat. No.3,476,266 is suitable for its intended purpose, it proposes to employ amanually operable drum for each of the controlled axes of themanipulator arm and presumably each of these drums is motor drivenduring the teaching operation to move the manipulator arm to differentdesired points to accomplish a certain programmed series of steps.Furthermore, in the arrangement shown in the DeVol patent, no facilitiesare provided for insuring that the manipulator arm does not move wildlyabout when power is first applied to the manipulator apparatus onstartup. Such an arrangement can be extremely dangerous to personnelusing the apparatus in the event that the pre viously programmed stepcalls for movement of' the arm in a path which would strike the operatoras he starts to perform a new teaching operation, or in the event thathe is in the area covered by the movement of the arm on startup on thatparticular morning.

It is, therefore, an object of the present invention to provide a newand improved recording or teaching arrangement for use in a manipulatorapparatus of the type which utilizes hydraulic microbit actuators aspower sources for moving the manipulator arm in its various controlledaxes.

It is a further object of the present invention to provide a new andimproved teaching arrangement for a manipulator apparatus of the typeutilizing hydraulic microbit actuators wherein facilities are providedfor controlling the series of hydraulic actuators in each axis toprevent unexpected or undesired movement of the arm on startup.

It is another object of the present invention to provide a new andimproved record-playback arrangement for manipulator apparatus of thetype utilizing hydraulic microbit actuators wherein a pulse sourcecommon to all axes is employed to control a series of electroniccounters which in turn control selective actuation of each series ofhydraulic microbit actuators to effect desired movements of the arm ineach of its controlled axes during the initial teaching operation. I I

It is another object of the present invention to provide a new andimproved record-playback arrangement for manipulator apparatus of thetype employing hy draulic microbit actuators wherein the position of themanipulator arm in each controlled axis is detected by employing limitswitch means associated with each actuator in each series, the outputfrom said limit switch means being employed to immediately set anelectronic counter which isemployed to control actuation of the microbitactuators during both the teaching operation and subsequent playbackoperations.

Briefly, in accordance with one aspect of the invention, a common pulsesource is employed to control counting in either direction of a seriesof electronic bidirectional counters which are provided for eachcontrolled axis of the manipulator arm. A stream of pulses from thiscommon pulse generator may thus be selectively applied to either theup-lead or down-lead of each counter so as to move the manipulator armto a desired position during the initial recording or teachingoperation. When the desired position is reached, the output of eachcounter is recorded on a suitable memory drum and this recorded signalmay then be employed during successive playback operations as a commandsignal to control movement of the manipulator arm to the desiredposition in each of the controlled axes thereof. On playback, therecorded signal is applied in parallel to the same electronic counterwhich is employed to control movement of the arm during the record orteaching operation and the binary related outputs of each counterareemployed to control solenoid operated valves which in turn controlactuation of the series of fluid pressure sensitive actuators which formeach hydraulic microbit actuator of the manipulator apparatus. Onplayback, the recorded memory drum signal is also applied to one inputof a comparator to the other input of which is supplied the binary codecombination of limit switch means associated with each actuator in theseries. Furthermore, all of the controlled axes of the manipulator maybe sequentially scanned during a multiplex cycleso that only a singlecomparator is required to provide the desired total coincidence signalwhich signifies that the next programmed step in the memory drum shouldbe selected.

The invention, both as to its organization and method of operation,together with further objects and advantages thereof, will best beunderstood by reference to the following specification taken inconnection with the accompanying drawings in which:

FIG. 1 is a schematic diagram, partly in block diagram form, of thecontrol system arrangement of the present invention for one of thecontrolled axes of a programmable manipulator arm, shown during theinitial teaching or recording operation;

FIG. 2 is a similar circuit diagram of the apparatus of FIG. 1 but shownin the playback or repeat mode; and

FIG. 3 is a schematic diagram of one of the stages of No, 3,661,051,wherein the manipulator arm is movable in a 'number'of controlled axesby means of hydraulic actuators under the control of command signalswhich are sequentially read from a memory drum, or the like. In saidDunne et al patent the hydraulic actuators are of the simple piston andcylinder type and are controlled by suitable solenoid operated valves,these valves in turn being controlled by means of a comparator systemwhich compares the binary coded output from an encoder geared to themovable member of the hydraulic actuator with a related binary codecommand signal from the memory drum.

In the arrangement of the present invention, a different type ofhydraulic actuator is employed, which may be termed an hydraulicmicrobit actuator, and is of the type shown in Devol U.S. Pat. No.3,476,266. One of these microbit actuators is shown generally in FIG. 1at as comprising a series of fluid pressure actuators which havedifferent binary related strokes so that binary coded signals may beapplied directly thereto to establish a predetermined distance. Moreparticularly, the microbit actuator 10 comprises a first cylinderportion 12 which is secured to an end flange 14 of the actuator. Amovable piston 16 is slidably mounted in the clyinder 12 and iscontrolled by means of a two-way solenoid operated valve 18, the valve18 being supplied from a suitable source of fluid pressure 20 andexhausting to a suitable sump 22. The stroke of the piston 16 is chosento be equal to the smallest unit of movement of the manipulator arm andthe piston 16 is integrally attached to the cylinder 24 of the next unitin the series of fluid pressure actuators. A piston 26 is slidablymounted within the cylinder 24 and is controlled by means of the two-waysolenoid operated valve 28, the valve 28 being supplied with pressurefrom the same pressure source 20 and exhausting to the same sump 22. Thestroke of the piston 26 is exactly twice that of the piston 16, so thatbinary related motions of the overall actuator may be achieved bycontrolling thesolenoid operated valves 18 and 28 in accordance with thebinary input.

The piston 26 is integrally connected to the cylinder portion 30 of thenext series related fluid pressure actuator, a piston 32 being slidablymounted within the cylinder 30 and having a stroke equal to twice thatof the piston 26. A similar two-way solenoid operated valve 34 isemployed to control movement of the piston 32 from one end of thecylinder 30 to the other.

In a similar manner an additional number of fluid pressure actuators maybe connected in series to the illustrated units, the piston of the endone of these actuators being connected to the end flange 36 of theoverall hydraulic microbit actuator. The flanges 14 and 36 are attachedto fixed and movable portions of the mechanism employed to move themanipulator arm in a particular axis, as described in detail in saidDunne et a] patent and in Devol U.S. Pat. No. 3,476,266.

In accordance with an important feature of the present invention, aseries of limit switches are associated with individual ones of theseries of fluid pressure actuators in the microbit actuator 10 and areemployed to provide feedback information indicative of the actualposition of the actuator 10 at any particular moment. More particularly,a microswitch 38 is secured to the cyclinder l2 and the contacts thereofare arranged to be closed by engagement with the left-hand edge of thecylinder 24 when the piston 16 is in its left-hand-most position asshown in FIG. 1. However, when'the piston 16 is actuated to the otherend of the cylinder 12, the contacts of the microswitch 38 are opened.In a similar manner, microswitches 40 and 42 are associated with thecylinders 24 and 30 respectively and additional microswitches areassociated with each of the other binary related fluid pressureactuators in the series making up the acutator 10. Accordingly, on theoutput conductors 44, 46 and 48, of the microswitches 38, 40 and 42,respectively, output signals appear in accordance with the on or offcondition of these microswitches which represent the physical positionof the pistons within the individual cylinders of the microbit actuator.In this connection it will be understood that a common connection (notshown) may be employed for one side of all of these microswitches or inthe alternative one side of each microswitch may be connected to groundthrough the illustrated cylinder and piston arrangement.

In accordance with a further important feature of the present invention,an oscillator 50 is provided which is common to all of the fiveillustrated axes of the manipulator apparatus, the output of theoscillator 50 being supplied to a suitable pulse shaper 52 so thatpulses suitable for actuation of the electronic bi-directional counterare provided. These pulses are supplied through a teach-repeat switch 54to a pair of teach control switches 56 and 58 when the switch 54 is inthe teach position. When the switch 54 is in the repeat position nopulses are supplied to the teach controls 56 and 58. However, when theapparatus is in the teach position one of the push buttons 56 may beclosed, for example, the button 56, in which case a stream of pulses issupplied to the count up lead 60 of an electronic bi-directional countermade up of a series of binary related stages 62, 64, 66, etc. On theother hand when the push button 58 is depressed this same stream ofpulses is supplied over a count-down input lead 68 to a different inputof the stages of the bi-directional electronic counter. The electricaloutput of each stage of this counter is employed to control a suitablesolenoid which actuates an associated two-way valve to control theposition of the piston in the associated section of the microbitactuator 10. Thus, the output of the first stage 62 is supplied to asolenoid 70 which controls movement of the two-way valve 18. The outputof the stage 64 is supplied to a solenoid 72 which controls the valve 28and the output of the stage 66 is supplied to a solenoid 74 whichcontrols the valve 34.

The teach control arrangement described thus far is provided for theout-in axis of the manipulator apparatus. In accordance with a furtherfeature of the invention, the common pulse source 52 is employed tosupply a stream of pulses to similar control apparatus for each of theother controlled axes of the manipulator. Thus, these pulses aresupplied during the teaching mode through the switch 54 to similarapparatus, indicated generally at for the swivel axis of the manipulatorarm, the positions of the various sections of the microbit actuatorassociated with this axis, which is similar to the microbit actuator 10,being provided on the limit switch output conductors 82. In a similarmanner, the pulses from the shaper 52 are supplied to the controlapparatus 84 for the down-up axis, to the apparatus 86 for the wristbend axis and to the apparatus 88 for the rotary axis of the manipulatorapparatus. Each of the microbit actuators associated with thesedifferent axes produce output signals which are supplied to theconductors 90, 92 and 94, respectively. A pair of directional controlpush buttons, similar to the push button 56 and 58, is provided for eachof the other four illustrated axes of the manipulator apparatus so thata stream of pulses from the common pulse shaper 52 may be supplied toeither desired input of the electronic counter provided for each ofthese axes, as described in detail heretofore in connection with theout-in axis. Accordingly, during the teaching mode when it is necessaryto move the manipulator arm to a desired position and record thisposition as a command signal on the associatedmemory drum of themanipulator apparatus, the push buttons 56, 58 in each of the controlledaxes are selectively actuated by depressing the same a length of timenecessary to cause the manipulator arm to move in that controlled axisby the required distance, as visually determined by the teachingoperator by visual inspection of the position of the manipulator arm.

Thus, if it is desired to move the arm a certain distance in the outdirection, the button 56 is depressed and a stream of pulses is suppliedover the lead 62 to step the electronic'counter comprising the stages62, 64, etc. As this counter is stepped to successively higher counts inresponse to each of the input pulses, the associated solenoids 70, 72,74, etc. control their associated two-way valves 18, 28 and 34 so thatthe various sections of the microbit actuator are moved so that anoverall movement in the out direction is produced at a rate determinedby the rate of occurrence of the pulses developed by the pulse shaper52. In this connection it will be understood that this pulse rate ischosen so that the manipulator arm will be moved smoothly to the desiredposition at a rate sufficiently slow that the operator is permitted byvisual inspection to determine when the end of the manipulator arm hasarrived at the desired position. It is also contemplated that thefrequency of the oscillator 50 may be varied by any suitable means wellknown in the art so that various slewing rates in the controlled axes ofthe manipulator apparatus may be provided. For example, in an actuator10 having ten binary related sections the smallest of which has a strokeof 0.1 inches, a pulse rate of 100 pulses per second may be employed toprovide a fast slewing rate during the initial phase of movement of thearm during the teaching operation and a slow-down operation may beeffected by simply changing the frequency of the oscillatorl50 to 10pulses per second as the end of the arm approaches the desired endposition. When the end of the manipulator arm has been programmed in allof the five controlled axes of the apparatus, the main record button 96of the manipulator apparatus is closed so that the outputs from all ofthe limit switches in each controlled axis are supplied through thetransfer control panel 98 to a shift register and may be supplied to therecording heads of the associated memory drum of the manipulatorapparatus, as described in detail in said Dunne et al patent. Referencemay be had to said Dunne et al patent for a complete and detaileddescription of the manner in which the recording of these signals duringthe teaching operation is effected. Accordingly, the desired positionsof the manipulator are, as represented by the limit switches associatedby each of the microbit actuators 10, are simultaneously recorded ascommand signals in the memory drum of the manipulator control apparatusfor each desired position of the manipulator arm, it being noted thatthe microswitch signals take the place of the digital encoder signalsprovided in the arrangement described in detail in said Dunne et alpatent. These limit switches thus provide in a simple and economicalmanner a feedback or encoder signal representative of the actualphysical position of the microbit actuator 10 which in turn representsthe position of the manipulator arm in that controlled axis.

Considering now the operation of the arrangement of the presentinvention during the playback or repeat mode of operation of themanipulator apparatus, and referring to FIG. 2, during playback nopulses are supplied to the input leads 60, 68 of the electronic counter.However, this counter is arranged so that any desired binary number maybe set into the counter by means of binary related signals applied inparallel to separate 1 and 0 inputs of each stage of the counter, thistype of electronic counter being conventionally referred to as apresettable down-up counter. More particularly, the binary coded commandsignal, which is derived from the memory drum and is stored in atemporary buffer storage register indicated generally at 100, issupplied to the individual stages of the electronic counter over theindicated conductors 102, 104, 106, etc. In this connection it will beunderstood that the manner in which the command signal is read from thememory drum and stored in the buffer register is described in detail insaid Dunne et al patent, and reference, may be had to the specificationof said patent for a more complete understanding of this readoutarrangement. A second section of the repeat cycle switch 54 is arrangedto supply an enabling signal over the conductor 108 to all of the stagesof the electronic counter, as will be described in more detailhereinafter in connection with FIG. 3. Accordingly, the command signalcorresponding to the first programmed step in the recorded program issupplied on an individual bit basis to the individual stages of theelectronic counter and the solenoids 70, 72, 74, etc. associated withthese stages are immediately energized in accordance with the individualbits of the first command signal binary number so that the microbitactuator 10 in energized to move the manipulator arm to the desiredposition. The command signal corresponding to the first out-in commandof the recorded program is also supplied by way of the conductors 102,104, 106, etc. to one section of a multiplex scanning switch indicatedgenerally at 110, the common output of this switch being supplied at oneinput to the comparator 112. Also, the output signals derived from thelimit switches 38, 40 and 42, etc. are supplied by way of the conductors44, 46 and 48, to one input 114 of a second multiplex scanning switchindicated generally at 116, the common output of this switch beingsupplied as the other input of the comparator 112. A distributorscanning switch 118 is provided at the output of the comparator 112 andsuccessively provides comparator output signals to a series offlip-flops 120, 122, 124, 126, and 128 corresponding to the fivecontrolled axes of the manipulator apparatus, the uppermost flip-flop120 corresponding to the illustrated out-in controlled axis of themanipulator. Accordingly, when the manipulator arm has been moved to thedesired position as indicated by coincidence of the command signaldeveloped on the conductors 44, 46 and 48, a comparator output signal isemployed to set the flip-flop 120 thereby indicating that movement inthe out-in axis has been completed. In a similar manner the scanningswitches 1 10, l 16 and 118 are successively connected to differentcommand and limit switch signals on the input side of the comparator andcontrol the corresponding flip-flop ,on the output side of thecomparator 112 so that movement in all five controlled axes is monitoredas these scanning switches are rotated. When all five of the flip-flops120 to 128, inclusive, are set, a five input ANDgate 130 is arranged todevelop an output signal which is supplied to a total coincidenceAND-gate 132 to which other output signals such as wait external, etc.may be supplied. A total coincidence signal is thus developed on theoutput conductor 134 when movement in all of the controlled axes and anyother options have been completed, as described in detail in said Dunneet a1 patent. In this connection it will be understood that the outputof the AND-gate 130 may be employed as an accuracy No. 1 signal andsuitable accuracy 2 and accuracy 3 coincidence circuits employed, ifdesired, as described in said Dunne et al patent, it being noted thatthe comparator 112 corresponds to the comparator 422 shown in said Dunneet al patent and may be associated with a suitable digital analogconverter (not shown), corresponding to the converter 456 of said Dunneet al patent, to provide suitable output signals for the flip-flops 120to 128, inclusive. In this connection it is also noted that gray tobinary code converters may be employed between the multiplex switches110 and 116 to the inputs of the comparator 112, as described in detailin said Dunne et al patent.

When a total coincidence signal is developed on the conductor 134, themanipulator control apparatus is arranged to sense another commandsignal recorded in the associated memory drum and the next commandsignal is supplied to the buffer register 100, as described in detail insaid Dunne et al patent. Accordingly, this next command signal is setinto the individual stages of the electronic counter associated with theoutin axis, as described in detail heretofore, and the microbit actuatoris moved to the desired position corresponding to this command signal.Coincidence is again indicated by a comparison of the limit switchsignals with this command signal, as described in detail heretofore. Ina similar manner command signals are supplied to all of the other fourcontrolled axes of the apparatus, one such controlled axis being shownin FIG. 2 as the wrist swivel command signal 136 and its associatedapparatus 138, the limit switch output and command signal output of theapparatus 138 being supplied to the second level of the multiplexscanning switches 110 and 116.

From the above description it will be understood that the manipulatorarm is moved to successive positions as determined by the binary codedcommand signals set into the electronic counters associated with each ofthe controlled axes of the manipulator. It will also be noted that themanipulator arm is left in a position corresponding to the last commandsignal when the apparatus is turned off and power is removed from themicrobit actuators 10. If a teaching operation is to be performed assoon as the apparatus is turned on the next morning, the manipulator armwill immediately be moved to the position corresponding to the commandsignal previously set into the electronic counter when power is suppliedto the hydraulic microbit actuators 10 on start-up. Accordingly, it ispossible that the teaching operator may be injured if the manipulatorarm is not otherwise controlled on start-up. To prevent such acondition, each stage of each one of the electronic counters providedfor each of the five controlled axes is arranged also to be controlledfrom a start-up pulse which is generated at the time power is initiallysupplied to the microbit actuators 10 and the presettable electroniccounter is immediately set to the actual physical position of each ofthese actuators on start-up by employing the limit switch signalsdirectly as input signals in place of the conventional command signalsderived from the memory drum.

More particularly, each of the stages of the presettable electroniccounter, such as the first stage shown in FIG. 3 of the drawings, isprovided with a pair of AND- gates and 142 to one input of which anenabling pulse is supplied over the conductor 144 whenever themanipulator apparatus is initially energized and power is supplied tothe microbit actuators 10. The signal from the limit switch 38 isapplied directly as the other input of the AND-gate 140 and through aninverter 146 as the other input of the AND-gate 142. Accordingly, assoon as an enabling pulse is developed on the conductor 144 an output isderived from either the AND- gate 140 or the AND-gate 142 and issupplied through the corresponding one of the OR-gates 148 or 150 toeither the set 1 or the set 0 terminal of the initial stage of thepresettable electronic counter. In a similar manner, each of the otherstages of this counter is immediately set to a position corresponding toone of the other limit switches 40, 42 when an enabling pulse isdeveloped on the conductor 144. Accordingly, as soon as the manipulatorapparatus is energized and power is supplied to the microbit actuators10, the limit switch signals are employed to set the presettableelectronic counter to the actual physical position of the arm onstart-up so that no movement of the manipulator arm can'occur. Either ateaching operation or a playback operation may now proceed without fearof being injured by initial movement of the manipulator arm on start-up.

Assuming that a teaching operation is performed after start-up, as soonas the teaching operation is completed and the teach-repeat switch isthrown to the repeat position, an enabling pulse is developed on therepeat conductor 108. This pulse is supplied as one input to a secondpair of AND-gates 152 and 154. The memory drum command signal on theconductor 102 is applied directly to the AND-gate 152 and through aninverter 156 to the AND-gate 154 so that an output is supplied to theset 1 or set 0 terminal of this stage of the presettable counter. In asimilar manner, the other stages of each counter are set by the signalson the conductors 104, 106, etc. The manipulator arm is then moved tothe programmed position, as described in detail heretofore. In thisconnection, it is noted that an enabling pulse is supplied to theconductor 144 only on start-up and hence the application of the limitswitch signals to the AND-gates 140 and 142 is ineffective to modify theoperation of the apparatus during the repeat mode of operation.

While there has been illustrated and described a single embodiment ofthe present invention, it will be apparent that various changes andmodifications thereof will occur to those skilled in the art. It isintended in the appended claims to cover all such changes andmodifications as fall within the true spirit and scope of the presentinvention.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. In a programmed manipulator, the combination of, a manipulator arm,power actuator means for moving said arm simultaneously along aplurality of axes, each of said power actuator means comprising aplurality of actuators, driving energy supply means, and selectivelyoperable elements for controlling the supply of driving energy to saidactuators, said actuators each having an extended state and a retractedstate and adapted to be driven by the driving energy of said supplymeans for assuming or maintaining either of said states in accordancewith the selective operation of said elements, said actuators beingfastened to one another to effect driving operation in either direction,means for detecting the expanded or retracted position of each of saidactuators and developing an electrical position signal correspondingthereto, presettable electronic counter means for controlling saidelements, and means for supplying said electrical position signals tosaid counter means to provide an initial setting of said counter meanscorresponding to the expanded or retracted states of each of saidactuators.

2. The combination of claim 1, which includes switch means forselectively supplying said electrical signals to said counter means, andmeans responsive to the application of driving energy to said actuatorsfor actuating said switch means, thereby to set said counter means to aninitial setting corresponding to the expanded or retracted states ofsaid actuators at the time said driving energy is applied thereto.

3. The combination of claim 1, wherein said detecting means comprises aseries of limit switches individually positioned to be operated by themovable member of one of said actuators, and means controlled by saidlimit switches for presetting the individual stages of said countermeans.

4. The combination of claim 1, wherein said counter means has count upand count down inputs, means for developing a stream of pulses occurringat a predetermined rate, and teach control means for selectivelysupplying said pulses to either said count up input or said count downinput of said counter means to increase or decrease the count therein,thereby to cause said manipulator arm to be moved smoothly by saidactuators to a desired position along one of said axes.

5. The combination of claim 4, wherein said detecting means comprises aseries of limit switches individually positioned to be operable by themovable member of one of said actuators, a memory storage arrangement,and means for recording the condition of said limit switches when saidmanipulator arm has been moved to said desired position.

6. The combination of claim 5, which includes playback means utilizingsaid recorded limit switch conditions as a command signal and also as apresetting signal for said counter means, and comparator means jointlyresponsive to said command signal and the respective conditions of saidlimit switches for developing a total coincidence signal when said limitswitch conditions all correspond to said command signal.

7. In a programmed manipulator, the combination of, manipulator arm,power actuator means for moving said arm simultaneously along aplurality of axes, each of said power actuator means comprising aplurality of actuators, driving energy supply means, and selectivelyoperable elements for controlling the supply of driving energy to saidactuators, said actuators each having an extended state and a retractedstate and adapted to be driven by the driving energy of said supplymeans for ments are controlled in accordance with the respective digitsof said first command signal, comparing means jointly responsive to saidfirst command signal and said detecting means for developing an outputsignal when the electrical signals developed by said detecting meanscorrespond to the respective digits of said first command signal, andmeans responsive to said output signal for selecting the next commandsignal in said series and supplying the same to said counter means andsaid comparing means.

8. The combination of claim 7, which includes means for sequentiallyconnecting said comparing means to different command and position signalcombinations corresponding to movement in different ones of said axesduring different periods in a repetitive multiplex scanning cycle.

9. The combination of claim 8, which includes a series of flip-flopcircuits one for each of said axes, means for distributing the output ofsaid comparing means to different ones of said flip-flop circuits duringdifferent periods of said scanning cycle, and means controlled by saidflip-flop circuits for developing a total coincidence signal when all ofsaid flip-flop circuits have been set in response to the output of saidcomparing means.

10. In a programmed manipulator, the combination of, a manipulator arm,power actuator means for moving said arm simultaneously along aplurality of axes, each of said power actuator means comprising aplurality of actuators, driving energy supply means, and selectivelyoperable elements for controlling the supply of driving energy to saidactuators, said actuators each having an extended state and a retractedstate and adapted to be driven by the driving energy of said supplymeans for assuming or maintaining either of said states in accordancewith the selective operation of said elements, said actuators beingfastened to one another to effect driving operation in either direction,an electronic counter corresponding to each of said controlled axes andeach having a count up and a count down input, means common to said axesfor developing a continuous stream of pulses, and teach control meansfor selectively applying said stream of pulses to either the count upinput or count down input of said counters, thereby to cause saidmanipulator arm to be moved smoothly to a desired position, and meansfor recording said desired position of said arm once it is achieved.

11. The combination of claim 10, wherein said last named means includesa series of limit switches individually associated with the actuators ofeach of said power actuator means and arranged to develop an electricalsignal corresponding to its physical position thereof.

1. In a programmed manipulator, the combination of, a manipulator arm,power actuator means for moving said arm simultaneously along aplurality of axes, each of said power actuator means comprising aplurality of actuators, driving energy supply means, and selectivelyoperable elements for controlling the supply of driving energy to saidactuators, said actuators each having an extended state and a retractedstate and adapted to be driven by the driving energy of said supplymeans for assuming or maintaining either of said states in accordancewith the selective operation of said elements, said actuators beingfastened to one another to effect driving operation in either direction,means for detecting the expanded or retracted position of each of saidactuators and developing an electrical position signal correspondingthereto, presettable electronic counter means for controlling saidelements, and means for supplying said electrical position signals tosaid counter means to provide an initial setting of said counter meanscorresponding to the expanded or retracted states of each of saidactuators.
 2. The combination of claim 1, which includes switch meansfor selectively supplying said electrical signals to said counter means,and means responsive to the application of driving energy to saidactuators for actuating said switch means, thereby to set said countermeans to an initial setting corresponding to the expanded or retractedstates of said actuators at the time said driving energy is appliedthereto.
 3. The combination of claim 1, wherein said detecting meanscomprises a series of limit switches individually positioned to beoperated by the movable member of one of said actuators, and meanscontrolled by said limit switches for presetting the individual stagesof said counter means.
 4. The combination of claim 1, wherein saidcounter means has count up and count down inputs, means for developing astream of pulses occurring at a predetermined rate, and teach controlmeans for selectively supplying said pulses to either said count upinput or said count down input of said counter means to increase ordecrease the count therein, thereby to cause said manipulator arm to bemoved smoothly by said actuators to a desired position along one of saidaxes.
 5. The combination of claim 4, wherein Said detecting meanscomprises a series of limit switches individually positioned to beoperable by the movable member of one of said actuators, a memorystorage arrangement, and means for recording the condition of said limitswitches when said manipulator arm has been moved to said desiredposition.
 6. The combination of claim 5, which includes playback meansutilizing said recorded limit switch conditions as a command signal andalso as a presetting signal for said counter means, and comparator meansjointly responsive to said command signal and the respective conditionsof said limit switches for developing a total coincidence signal whensaid limit switch conditions all correspond to said command signal. 7.In a programmed manipulator, the combination of, manipulator arm, poweractuator means for moving said arm simultaneously along a plurality ofaxes, each of said power actuator means comprising a plurality ofactuators, driving energy supply means, and selectively operableelements for controlling the supply of driving energy to said actuators,said actuators each having an extended state and a retracted state andadapted to be driven by the driving energy of said supply means forassuming or maintaining either of said states in accordance with theselective operation of said elements, said actuators being fastened toone another to effect driving operation in either direction, means fordetecting the expanded or retracted position of each of said actuatorsand developing a group of binary related electrical position signalscorresponding thereto, presettable electronic counter means forcontrolling said elements, means for sequentially developing a series ofdigital command signals, means for supplying the first one of saidcommand signals in said series to said counter means so that saidselectively operable elements are controlled in accordance with therespective digits of said first command signal, comparing means jointlyresponsive to said first command signal and said detecting means fordeveloping an output signal when the electrical signals developed bysaid detecting means correspond to the respective digits of said firstcommand signal, and means responsive to said output signal for selectingthe next command signal in said series and supplying the same to saidcounter means and said comparing means.
 8. The combination of claim 7,which includes means for sequentially connecting said comparing means todifferent command and position signal combinations corresponding tomovement in different ones of said axes during different periods in arepetitive multiplex scanning cycle.
 9. The combination of claim 8,which includes a series of flip-flop circuits one for each of said axes,means for distributing the output of said comparing means to differentones of said flip-flop circuits during different periods of saidscanning cycle, and means controlled by said flip-flop circuits fordeveloping a total coincidence signal when all of said flip-flopcircuits have been set in response to the output of said comparingmeans.
 10. In a programmed manipulator, the combination of, amanipulator arm, power actuator means for moving said arm simultaneouslyalong a plurality of axes, each of said power actuator means comprisinga plurality of actuators, driving energy supply means, and selectivelyoperable elements for controlling the supply of driving energy to saidactuators, said actuators each having an extended state and a retractedstate and adapted to be driven by the driving energy of said supplymeans for assuming or maintaining either of said states in accordancewith the selective operation of said elements, said actuators beingfastened to one another to effect driving operation in either direction,an electronic counter corresponding to each of said controlled axes andeach having a count up and a count down input, means common to said axesfor developing a continuous stream of pulses, and teach control meansfor selectively applying said stream of pulses to either the count upinput or count down input of said counters, thereby to cause saidmanipulator arm to be moved smoothly to a desired position, and meansfor recording said desired position of said arm once it is achieved. 11.The combination of claim 10, wherein said last named means includes aseries of limit switches individually associated with the actuators ofeach of said power actuator means and arranged to develop an electricalsignal corresponding to its physical position thereof.